I gave this a 4 out of 5 only because this particular set is best if not used daily (in my opinion). I introduced these to our 4yo and she buzzed right through them pretty easily. I will try these with our 3yo a little earlier. Past the first time, you will have to pay attention to make sure they are sounding out the letters rather than just looking at the picture and recalling which word is being presented. I remind her to sound each letter out phonetically when I see her drifting. These are definitely a great investment in your child's learning process. Our girls get excited any time I bring out the box of flash cards!

I got this for my son when he was three. It helped him understand the logical sequence for a picture (e.g.; head comes first, followed by body and tail) in addition to learning the spelling. He'd typically start with the colorful side first and once he forms the three-letter word, he'd be curious to find out what happens in the one-colored side.